'\"
'\" Generated from file 'tcllib_coroutine\&.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2010-2015 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>
'\"
.TH "coroutine" n 1\&.2 tcllib "Coroutine utilities"
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.BS
.SH NAME
coroutine \- Coroutine based event and IO handling
.SH SYNOPSIS
package require \fBTcl  8\&.6\fR
.sp
package require \fBcoroutine  1\&.2\fR
.sp
\fBcoroutine::util after\fR \fIdelay\fR
.sp
\fBcoroutine::util await\fR \fIvarname\fR\&.\&.\&.
.sp
\fBcoroutine::util create\fR \fIarg\fR\&.\&.\&.
.sp
\fBcoroutine::util exit\fR ?\fIstatus\fR?
.sp
\fBcoroutine::util gets\fR \fIchan\fR ?\fIvarname\fR?
.sp
\fBcoroutine::util gets_safety\fR \fIchan\fR \fIlimit\fR \fIvarname\fR
.sp
\fBcoroutine::util global\fR \fIvarname\fR\&.\&.\&.
.sp
\fBcoroutine::util read\fR \fB-nonewline\fR \fIchan\fR ?\fIn\fR?
.sp
\fBcoroutine::util update\fR ?\fBidletasks\fR?
.sp
\fBcoroutine::util vwait\fR \fIvarname\fR
.sp
.BE
.SH DESCRIPTION
The \fBcoroutine\fR package provides coroutine-aware
implementations of various event- and channel related commands\&. It can
be in multiple modes:
.IP [1]
Call the commands through their ensemble, in code which is
explicitly written for use within coroutines\&.
.IP [2]
Import the commands into a namespace, either directly, or
through \fBnamespace path\fR\&. This allows the use from within code
which is not coroutine-aware per se and restricted to specific
namespaces\&.
.PP
A more agressive form of making code coroutine-oblivious than point 2
above is available through the package \fBcoroutine::auto\fR,
which intercepts the relevant builtin commands and changes their
implementation dependending on the context they are run in, i\&.e\&.
inside or outside of a coroutine\&.
.SH API
All the commands listed below are synchronous with respect to the
coroutine invoking them, i\&.e\&. this coroutine blocks until the result
is available\&. The overall eventloop is not blocked however\&.
.TP
\fBcoroutine::util after\fR \fIdelay\fR
This command delays the coroutine invoking it by \fIdelay\fR
milliseconds\&.
.TP
\fBcoroutine::util await\fR \fIvarname\fR\&.\&.\&.
This command is an extension form of the \fBcoroutine::util vwait\fR
command (see below) which waits on a write to one of many named
namespace variables\&.
.TP
\fBcoroutine::util create\fR \fIarg\fR\&.\&.\&.
This command creates a new coroutine with an automatically assigned
name and causes it to run the code specified by the arguments\&.
.TP
\fBcoroutine::util exit\fR ?\fIstatus\fR?
This command exits the current coroutine, causing it to return
\fIstatus\fR\&. If no status was specified the default \fI0\fR is
returned\&.
.TP
\fBcoroutine::util gets\fR \fIchan\fR ?\fIvarname\fR?
This command reads a line from the channel \fIchan\fR and returns it
either as its result, or, if a \fIvarname\fR was specified, writes it
to the named variable and returns the number of characters read\&.
.TP
\fBcoroutine::util gets_safety\fR \fIchan\fR \fIlimit\fR \fIvarname\fR
This command reads a line from the channel \fIchan\fR up to size \fIlimit\fR
and stores the result in \fIvarname\fR\&. Of \fIlimit\fR is reached before the
set first newline, an error is thrown\&. The command returns the number of
characters read\&.
.TP
\fBcoroutine::util global\fR \fIvarname\fR\&.\&.\&.
This command imports the named global variables of the coroutine into
the current scope\&. From the technical point of view these variables
reside in level \fB#1\fR of the Tcl stack\&. I\&.e\&. these are not the
regular global variable in to the global namespace, and each coroutine
can have their own set, independent of all others\&.
.TP
\fBcoroutine::util read\fR \fB-nonewline\fR \fIchan\fR ?\fIn\fR?
This command reads \fIn\fR characters from the channel \fIchan\fR and
returns them as its result\&. If \fIn\fR is not specified the command
will read the channel until EOF is reached\&.
.TP
\fBcoroutine::util update\fR ?\fBidletasks\fR?
This command causes the coroutine invoking it to run pending events or
idle handlers before proceeding\&.
.TP
\fBcoroutine::util vwait\fR \fIvarname\fR
This command causes the coroutine calling it to wait for a write to
the named namespace variable \fIvarname\fR\&.
.PP
.SH "BUGS, IDEAS, FEEDBACK"
This document, and the package it describes, will undoubtedly contain
bugs and other problems\&.
Please report such in the category \fIcoroutine\fR of the
\fITcllib Trackers\fR [http://core\&.tcl\&.tk/tcllib/reportlist]\&.
Please also report any ideas for enhancements you may have for either
package and/or documentation\&.
.PP
When proposing code changes, please provide \fIunified diffs\fR,
i\&.e the output of \fBdiff -u\fR\&.
.PP
Note further that \fIattachments\fR are strongly preferred over
inlined patches\&. Attachments can be made by going to the \fBEdit\fR
form of the ticket immediately after its creation, and then using the
left-most button in the secondary navigation bar\&.
.SH KEYWORDS
after, channel, coroutine, events, exit, gets, global, green threads, read, threads, update, vwait
.SH CATEGORY
Coroutine
.SH COPYRIGHT
.nf
Copyright (c) 2010-2015 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>

.fi
